I have both with Viper connects sat on board and they are both performers but so is the Ultra Se with a Mamba that I have as well.
Took 4 shots at a 20 mm spinner at 60 yards this weekend with the regal and hit it twice which certainly put a smile on my face not being the greatest shot in the world.
I had the HW100 and Ultra se with me as well and was taking spinners and targets out to 50 yards with ease. The only reason I didn't go for 60 yards with these was the fact I had run the air down in them shooting at various other distances but I fully expect that both could have performed the same as the regal.
Each of them have their quirks but I am not that fussy and like shooting with any of them, I also have a 13 year old Theoben SLR98 which is still shooting at 11.4ft/lbs and has never been serviced, partly because it has been stored in a cupboard for 12 of those years ........