Does the clutch actually slip or does he just suspect the clutch because of the 5th gear problem? as its far more likeley to be a combination of the bushes and engine mounts

If they're sorting things out and they did a good job of the engine then maybe you should stick with them

better the devil you know and all that, just be sure you know or have a good idea what needs and specify what you want done before you give it to them

As for the electrics, I'm sure you used to them by now, it'll probably fix itself
