NMRA British Region Forum

I am new to n gauge and am building a small (2300mm x 1700mm) end to end layout using Peco track.
They have Code 80 and Code 55 track; which is best as at present I have no track so an starting from scratch.
I intend to have 18 inch curves (457mm); the largest locomotive I have is an N Scale Steam Collection Berkshire for which they recommend 18 inch curves; woud it go round 15 inch curves (381mm), albeit slowly?
An 18 inch curve is Ok for my proposed track plan but 15 inch would save space.
Any help would be greatly appreciated.
Thank you.

My researches reveal that there is no significant differences between Codes 80 and 55 but that Code 55 gives greater realism and that all stock will run on Code 80 whereas some older stuff may not depending upon wheel profile.
regarding my Berkshire I have got no further.
Can anyone please comment or help? I am a total newcomer to N gauge.