I have Not yet Had To change the battery in my old Alesis quad +
i have had to change the battery in my korg keyboard twice in roughly 20years
the problem is when changing a battery in the keyboard all the saved internal settings are lost
and have to be reloaded, via a midi data dump .which is not a problem has i have them saved on a seperate disc.
i would imagine it is the same with alesis quads ?
so my advice would be to get your quads internal memory backed up on to disc or whatever media you use.
then if you do have any problems with with battery failure or changing the internal battery.
you can just load all your settings back into your quad.
Back to the original question i have a Zoom 508, alesis quad+ & zoom g2
i prefer the zoom g2 ,followed by the zoom 508, then the alesis quadraverb+
but im not a lead guitarist i just dable so realy its just my personal preference as what sounds best to me.
il stick to the bass , no effects, whammy bars , or vox amps .to confuse me.
regards
Jay