If you can find it in your area Gunzilla works great on lead and cleans great. It a CLP (cleans, lubricates and protects) Low odor, non-flammable, no ammonia, non-corrosive, bio-based formula, no petroleum or water.
IMHO the Wildcat and Crown are pretty bullet proof. The Impact can be a little fussy but if you like to tune and tinker is a great airgun. The modular platform to switch calibers or just liners is a great option to have
I have used both The Oring Store and Orings and more and like both. The Oring Store is a little easier to navigate for me, great customer support, stocks Urethane Orings but has a flat rate shipping which for a small order makes it a little expensive. Orings and More has free shipping at $15 and...