Was wondering what is the difference between these engines when it comes to ease of tuning, power performance and life of engine, what's different inside?

Thanks

lower head,ceramic bearings,more officien timing and new piston (last's longer)

Truth be told, unless you're an expert engine tuner that always gets 100% out of the engine, you probably will not notice a difference between the engines.
A properly tuned basic plus 4 engine will not be the reason why you lost the race.

im not an expert tuner but i noticed a difference. it def. has a smoother bottom end and more top end.

Jeff if you can get the 4C team. It's the best version of the 21-4 out to date. I would wait and see what comes out after the worlds. Rumor has it there will be some revisions. Maybe just a new head.

I have the team toro and the billet piston is really nice and has kept compression longer than the older piston, that makes it worth the extra cash..

the team engines all have the billet piston....