It's all good until you realize you need those Whitworth sockets to do a paying job for a customer, who has a dozen fellow British iron fools, er, affecionados, and figured "Oh, I'll NEVER use those stupid British tools" so you sold them at auction a year before... and those big money people who play the Jag and Jensen symphony of broken **** say "Don't bother, they don't know what they're doing, they don't even have PROPER wrenches"...
Sure, I used to have a set that I could do everything on a bug short of a full transaxle rebuild (and I could even fake that depending on year) in my carry-around 50 caliber cans... but I realize when my paycheck is on the line I need at least a minimal set of "bring it on" tools... Including, yes, even Whitworth, and oddball Metric taps and dies, and ... because you never know if today is going to be tuning up the bosses AMC Concord, replacing the ceramic cylinders on a Bean ag pump, replacing the whirleygig points on your effing Lucas magneto to get your bike running to get you to your folks for Christmas, helping your bud with his 1972 Suzuki (if you know, you KNOW) because he stripped 3 of those oddball threaded effing case screws... or telling the guy on the phone "Sure, I can get those SU carbs sync'd and smooth... bring money!"...
My go to tools fit in a pair of tall 26" tool chests... and I don't leave home without them!