They are both good in their own way, the R10 is light and robust with a higher shot count, in .22 they like all of the JSB pellets, I would favour either the 15,9gn Exact (AA field) or if you wanted the flattest shooting highest velocity go for the Exact RS (Falcon accuracy) both these work so well in the .22 BSA barrel don't even bother trying any others.
Keep the pellet probe o ring lubed, a drop of oil each time you fill the gun will give it a longer life, let it go dry and it wears very quickly! with practice they are easy to replace, doesn't require stripping but a bit fiddly first time!
The reg in the R10 is a soft seal reg as is the HW too, so it is better like the HW to only fill the gun to 200 bar, 230 as is quoted as max fill pressure stresses the reg a bit, from 200 bar down they are fine.
The HW has probably the best Magazine system and also cannot be double loaded if it is cocked and you forget and cock it again, it will still only have one pellet in the barrel, most others inc the R10 would then have 2 in the barrel. The .22 HW100 barrel is unusual in that it only has 6 rifling lands, so this barrel prefers a harder pellet to get a good hold in the rifling, the H+N FTT has always in my experience been the best in the this rifle.
If the HW has any fault I would say that from the factory they are too heavily greased in the hammer, this can cause a slight power drop in very cold weather as the grease thickens slowing the hammer.
If both the rifles are in good fettle either will do what you expect of them.
HFT, for people with only 2 buttucks!
VooDoo TwoTwo The next chapter.