Hi Kevin, did you ever have it checked out or do you just work around it by changing gear and pushing through it. The mechanics who did my DMF and clutch, road tested it yesterday, disconnected the prop and checked out the universal joints, the engine mountings, pushed the block back a tad to try and remove any slackness, but admitted that they didn't think that would resolve it. they thought that it may possibly be down to something at the engine end, maybe a pulley or belt about to go causing slipping and vibration. They suggested I visit my local mechanic as their forte is gearboxes and clutches. They spent about 2 hours on my car at no charge.
They were recommended to me by my local garage, and for gearboxes/clutches I'd recommend them. Reasonable prices.
A1 Gearboxes, St Neots, Cambs.