Although I don't dispute the quality of these guns, they are all in a similar price bracket!!!! (£600-£800)
I would suggest something like the following;
Top end - S410/HW100t/Rapid
Middle Range - BSA Ultra/AA S200
Lower End - BSA Lightening XL
Budget - Any decent second hand springer (BSA, Webley, Weihrauch, etc, etc)
I might aswell join in
Top end - Daystate air wolf / Theoben rapid / FX Verminator
Middle range - S400 series / BSA R10 / HW100
Lower end - HW90 / Webley longbow / BSA lightning