Well, while there are similarities, they are two different beasts.
The neck on the EB JPM is flatter and smaller feeling than the Ibanez. *Some don't like the smaller neck on the EB model so you're going to have to determine what you are comfortable with. *I like the fact that they are different feeling, as it gives me more variety in my guitars. *The necks on the EBs come with the oil/gunwax finish which is ultra-smooth and easy to play on. *Some Ibanez JPMs have a laminate finish and some don't. *I used steel wool on my Ibanez which had a laminate finish cause I just don't like that sort of finish. *Made it play much better to me.
The pickups, while based on the same Air Norton and Steve's Special, are not the same sounding. *When I did an A/B comparison in my amp, the EB's pickups are definitely hotter and I had to back off on the gain. *The Ibanez's pickups are definitely hot enough for my tastes, but if I use the EB and Ibanez on the same amp settings they are really different sounding. *The neck pickups are more similar in both guitars than the bridge PUs, I would say.
Specifically regarding your tremelo question, I was very happy with the EB trem. *It's a completely new one for EB and it has the rear routing and smooth surface to rest your hand on. *It's a little stiffer than my lo-pros, but not that much. *In overall feel, I don't think it's that different from a lo-pro and I've heard other lo-pro users say the same and that they were pleasantly surprised. *However, it's still only single locking with Schaller locks and if you don't think that is enough for your trem use, then that's worth considering. *Mine never goes out of tune despite a few dive bombs here and there, but I don't do anything really abusive to the trem like some might. *I still dig my lo-pros, but having a couple of guitars that are so easy to either restring or detune has been great too.
Playability-wise, I think both guitars are fantastic and that's why I ended up with them. *I am also a huge fan of the JPM knob/switch layout like all of JP's guitars and Rob Balducci's custom models. *I was very skeptical with the EB model at first, but loved it when I played them at NAMM - especially the 7 string. *It is just unreal. *Quality-wise, based on my own personal experience with the guitars I've owned, my EB models came absolutely perfect from the factory. *EB has great QC and it shows. *I've had a couple of fret problems with one Ibanez JPM and no problems with 2 other Ibanez JPMs.
That's my experience so far.