How easy is it to fit an undertray? And is it worth the hassle?

I wouldn't really bother with it tbh, my old gp didn't have one and it was fine even though it was lowered

I wouldnt bother, i took mine off my tjet about a year ago and couldnt be bothered to put it back on. It makes no noticeble difference

Cheers, thanks for replies

It's for aerodynamics so why wouldn't it make a difference?

Ditto Old Engineer ... why would they waste money designing, making and fitting it ... its design plan is to change the airflow to aid mpg. Not having it on (or not/forgetting to replace it after working on the car) may not be too noticable, but it was there for a reason....