"Backup" so you have something, nice.
Have a 9-10 year old "Vevor" (black in color) still going strong, still have the rebuild kit it came with.
Naturally QC can change but having purchased the 1st hill (pos ! but they did improve) when released - freedom from suba tanks amazing. Owned the 1st & second FX pumps. Had a benjamin for 1 day, awful .
Paid something like $59 for the Vevor and it is smoother and easier to use than any of the others. Does seem to take a few more strokes on big bottles from empty. 500cc Blue FX 500 strokes even, vevor 500cc 540 or so stokes. (not counting refilling the hose after bleeding & cool down) but if you have some air in your rig lot's less pumping.
It is said all the pumps as many airguns (think snowpaek) are made in 1 or 2 factories then re-labed for whomever.
Neighbor got one (something Silver you were supposed to poor water into the tube for cooling) which was HARD to use days 1 and honked. Used about twice before he showed up. We took it apart in minutes and fairly well NO dry dry dry seals/0-roings. Proper lubing w/out changing anything & put back together and he has used in several times a week for several years.
Naturally lot's of hand pump posts here:
https://www.airgunnation.com/forums/tanks-pumps-compressors.23287/ Remember TECHNIQUE and you'll likely have no issues with the value (correctly) priced units.
John
What is you other air source?