Heller's 1/35 Leclerc depicts a very early model, and has a number of little annoying defects.. The tracks are not very good, and the hexagonal holes of the grenade launchers are badly represented. Those are not easy to correct!
Terre Modèles have a resin kit to bring the Heller kit to the T5-T8 variants (the latest in service). Metal tracks are also available. The T5 was used in the Balkans, while the T6 is still very well documented on the net. Edward have a PE set that will advantageously replace the set given in the Heller kit!
Here's a link to a site that has tons of info on French AFVs including the Leclerc, with dozens of detail pictures (from the prototype to the T6 variant). For info, the Leclerc 'Serie 1' include the T1 to T5 production series, T1 and T2 being pre-production vehicles (I think Heller's kit is a T2). 'Serie 2' includes the T6 to T9 production series (the T9 are not in service yet).
http://www.chars-francais.net/
As far as the other Heller kits are concerned, unlike the Leclerc which is a early '90s kit, all the others are from the '70s. They are overly complicated in my eyes, with too many parts. The detail is OK, but could be improved upon. The plastic is soft. Still nothing to deter you if you really want 1/35 French AFVs...!
By the way, Trumperter's Leclerc is not much better than Heller's...