So I'm getting round to refurbing the ace on my other disco, and want to replace all bushes as a precautionary measure. Just curious if anyone has used OEM bushes for the ram etc or if its better to steer clear and go genuine? OEM is around £7 and genuine being £30 as one example of the ram end bush. Was hoping I could split the rams as I had a lot of metal fragments in the system from the block mod, but seems they are crimped units..

OEM is genuine without the box. Go OEM.

I'm doing mine soon so I would be interested to hear what problems you have. Do you need a press for those bushes or just a vice?

I have done them before, I did use a hydraulic press if I recall, although a vice may possibly do them, I didn't change them all. Can usually find some shop or somewhere with a press who will do it for next to nothing. As for the quality of bushes, the main bush that takes a lot of force (number 9 in the picture) varies a hell of a lot in price, from £10 for aftermarket, £60 for OEM and £90 for genuine... Don't be fooled by OEM parts though, I'd say it's a 50/50 chance with landrover parts if they are actually true OEM. If I recall I fitted the £10 ones to my last setup, but the disco got crashed about 3k miles later and if I recall that bush was already quite loose, can't remember for certain though. I did a write up on replacing them all here
https://www.landyzone.co.uk/land-rover/complete-ace-renewal-with-pictures-ongoing.333344/

I need to refurb my front ARB sometime

Rear was new three years ago as it was only £60