Simple Isolator Valve Replacement

[caveman2]

I have a broken cistern and the replacement doesn't fit perfectly with the hard coppered feed. I have a an isolator valve (40 yo) that doesn't close completely and I therefor wish to change that at the same time as plumbing in the new bottom fill cistern valve.
The simplest way (I see) is a flat faced isolator valve https://www.toolstation.com/flat-faced-male-straight-isolating-valve/p95064 and a
https://www.toolstation.com/flexi-hose-300mm/p24989? Are these cheap components fail safe or should I buy better. Ideally I would like a lever rather than a screw on the isolator, but I cannot source one easy with a flat face. I could but a 15mm x 15mm Pegler say with a lever and put a

Tap Tail Adaptors

These two tap tail adaptors give you the connections you need to fit your flexible tap tails with 15 mm isolation valves. The helical screw threads fix tightly onto the tap tail to make installation easy. The small size ensures you save space around the fitting and simplifies your set-up. The...

www.toolstation.com

adaptor and connect hose to that.
Is that preferable although introducing another weak point for leaks.

 

[oldbuffer]

1. Personally I'd use the adaptors and a decent lever or butterfly (which might fit more easily) valve. The cheap isolation valves often don't last well and leak as soon as used after a few years of installation.
2. A "flexi", provided it is a decent quality and preferably WRAS approved, should be OK. Make sure you fit it correctly with only gentle curves and no kinks.

 

[caveman2]

The only 1/2" x 1/2" Flexi Hose I found was the cheapo from Toolstation. I'll continue looking and find a WRAS approved one. Thanks.