I have used spell points before, but mind once the party gets ahold of the heal spell or anything curing fatigue as this restores spell points. Then what you have is Energizer casters who can just keep going and going and going... This requires some tweaking unless your whole party is spellcasters and you don't mind the party not sleeping. Ever.
Magic recharge was fun, as the party had a bit more restriction on what and when it could cast certain spells. However, with this variant there's even less burnout on the casters and they don't even fatigue when they're all out. Indeed, odds are they'll never be all out and at least have something to throw at you.
Hex grid was what I first started playing on (lacked a square map). I liked it except for the complexity of buildings (does this half square have enough space...?). It seems more suited to flight rules than anything else.
The battle sorceror is balanced but notable weaker, since their specialization is broken in favor of a more rounded character. My players and I are a fan of the cloistered cleric because BAB and health are worth the skill points and access to all knowledge skills to us. As a DM, I've really enjoyed the paladin variants for their story usefulness (no longer constrained to LG "I'll save you Penelope!"), and the switch of fighters without feats and sneak attack as well as rogues without sneak attack but with feats.
The prestigious character classes are split. I like the bard, ranger and paladin being accessible at higher levels and contributing to one's caster level but some of my players prefer them as base classes (I suspect this is because now they have requirements). Ultimately I've houseruled that chronologically, games before year X in my game have normal paladins/bards/rangers and games past year X have only the prestigious variety. So far, it's working well.
I've made a gestalt character for a one-on-one game where the PC was playing an overpowered class from an online source. They seem well balanced enough, but we haven't gotten into a great deal of the story yet, let alone combat between the two.
All of that out on the table, I playtested each and every one of them before introducing them into a game. Spell points and magic recharge are tricky, and a huge change for both the PCs and the DM. Heal is a sixth/seventh level spell and once they get that, then the only reason they would ever rest is to swap out spells (if that). Powerthirst, anyone?