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Xtar Dragon VP4 Plus vs Opus BT-C3100 thoughts



Continuing the discussion from Any Opus BT-C3100 User's here?:

Overall, I strongly recommend (and prefer) the Opus BT-C3100. For a few reasons.

For starters, given that they seem pretty comparable on build quality, it really comes down to features and implementation as the deciding factor. (The price difference is a very nice bonus, but honestly, even if the Dragon was the same price as the BT-C3100, I’d still choose the 3100.)

The biggest selling point (to most I’m sure) is the 2amp charging slots (only the outer slots) on the Dragon. The problem I have with that is, barring a “one off, emergency charge” situation, IMO that function should absolutely not be used as an every day habit, because you’ll noticeably limit the life of your batteries (read as: total number of charge cycles). So might as well not even have the feature IMO. (As 1amp still charges really quickly, and they both are capable of that.) With that out of the way…

The Opus has a HUGE points in its favor that the Dragon can’t do!

  • independent slot control (the Dragon only works in pairs)

Because of this independence, you can:

  • do a discharge/refresh on a battery (or two, or three…) while still charging other batteries in the remaining slot(s)! (The Dragon only operates in one mode at a time: if you want to charge, ALL slots are for charging, if you want to refresh a single, or a pair, etc… ALL slots are for refreshing. You cannot mix modes on the Dragon! (at least according to video review - cited below).

On the Opus, I can, in any slot, and in any combination!

This is a very useful function (being able to simultaneously charge (in my case) a set, while refreshing another set. Especially considering the length of time it takes to do a single refresh cycle. Unless you have a second charger (or a multitude of batteries in reserve) this is a HUGE convenience that should not be taken lightly.
IMO a refresh should be done once approx. every 4-6 months (depending on how “rough” one is on them).

The next thing is the active fan. Heat being the leading cause of premature death of even well-designed electronics, the Opus includes a temperature activated fan (whereas the Dragon has no active cooling).
This not only extends the life of the charger components (device itself), but draws heat away from the underside of the chassis directly under the batteries, another thoughtful way of extending the life of the batteries. (Lower battery Temps = longer battery life)

There’s a whole host of reasons (and I may elaborate more later, as I’m being pressed for time ATM), but these are two of the biggest IMO (offhand) why I think the Opus is a much better unit, again with the bonus of being more cost effective.

There’s a couple of good videos I’ll link, and Phil raises some nice points (and is very concise for a change lol [unlike this post ironically, LOVE YA Phil!]) but I’d recommend watching both (about the Dragon), as there’s points I’m not pointing out here that may be relevant to some.

There are a select few reasons (very few) that one might prefer the Dragon though:

  • one is it’s footprint. It easily allows for 4 large batteries (ie: 20700) installed and charging simultaneously. (The Opus only allows 2 26650, due to physical size limitations)

  • another is the 3s LIPO pack convenience connector.

Other than those two points though, there’s really no competition IMO.

Phil’s thoughts (ends at the 15m mark)

A deeper look into the Dragon (and the point that it’s either “charge or refresh” affects all 4 slots simultaneously):


WoW, The DUDE ABIDES!!! You are way awesome (cool). Thanks for that bro. Totally appreciate you. I should have looked up the Opus before I asked. You da Man.


Happy to offer the opinion. =)


Do you have any opinions on the Opus BT 3400? I’m not sure what the differences are between it and the 3100 other than a higher price tag and the included car charger. Thanks in advance for any information you might have!


According to a third party relay (forum exchange), there is no longer a difference… As long as you purchase a v2.2 of the BT-C3100.


The main thing is as you mentioned, which equates to a $15 car charger accessory. While you might find one cheaper (car adapter), at least this saves you the time, hassles, and aggravation in trying to find the right adapter (with correct polarity, wire gauge to support the high current this thing can eat, etc). So all depends on what you want/need. :wink:

Since the v2.2 is readily available these days (it wasn’t 2 years ago), I’d pocket the savings, as it’s easier to carry a spare set (in a protective case) than lug around a charger in a vehicle (unless you spend a substantial amount of time on the road of course).

BT-C3100 specs

Reasonable $38 on Amazon, cheaper at GearBest, but with Amazon’s shipping, and great customer service, I know where I’d purchase. :wink:


Thanks so much for the thoughtful response! I already own an Opus BT 3100 V2.2 and it has been a wonderful charger over the past couple of years. I’ve been contemplating buying a second one (I go through a lot of batteries plus a back up is never a bad idea) and I can’t really see myself needing to use it in the car, so I’ll just stick with the 3100 V2.2 unless I happen upon a great sale on the 3400.