...I've had the car back for a day and a half and I've just realised my opinion is kind of useless!
I've never driven a 156 that didn't have something broken, so I've no idea if eibach have improved the handling or not.
That being said, I'll just describe what I think its like.. First off the clutch was replaced along with the gear box, I know this has nothing to do with the OP thread but I was blown away with the difference that can be had from going from a 124000 mile old clutch and gearbox to a new clutch and a gearbox with 40k on it. Its the lightest clutch I've ever used (and I'm including a raft of motorbikes I've owned in that!) I thought it was broken, I would have to equate it to bending grass on the pressure required front....
I almost forgot to check what the new ARB's were like I was so surprised! But of course I did. First off all the Knocks and creeks have gone as you might expect, the body roll is reduced but still present, I feel the car is now connected to the rear as before it was just dragging it around, this manifests it's self in an on rails effect - This is a good thing btw! Normally when you weave a car in the road it will feel as though the rear wheels are cutting the corner (because they are) hence all the 'feel' will come from the front, first thing I noticed with the eibach ARB's on is the rear 'feels' like its tracing the front wheels path like it's on rails. this was a bit disconcerting at first, but now I already don't notice it. Bearing in mind I have standard wheels and suspension, cornering is a joy, much improved, the balance mid corner that made me love this car in the first place is still there. Oh, btw my rear ARB was set to the 'unstiff' setting of the 2 when fitted, I would say its ok for normal fast use but if I were pushing harder I would want more over steer, throttle on hard through a corner will reveal under steer but go in hard on the breaks or with a little lift off the gas and the delightful and predictable over steer will result. The only thing stopping me going crazy for this ARB + Meyle combination is that fitting them has made my steering heavier, this in turn has robbed me of some of the feel I used to get through the wheel! This is not a deal breaker and I would still have done it if I'd known, rather it has revealed the next step in perfecting the handling of this car. Also revealed is the need for bigger lighter wheels IMO- to reduce the body roll, keep cornering flat and improve feel..., which in turn I'm sure will highlight the need for suspension upgrades.
To you guys speculating as to what I've spent fixing this car I say... £4000 including buying the car for £780.
Anyone thinking of buying Eibach ARB's and Meyle HD drop links, go for it, I've had no issues with the fit/ rubbing or touching of any other components. the cost of fitting standard ARB's and drop links was going to be about £425. fitted the Eibach and Meyle combo cost me £530. The fact that the 'upgrades' will defiantly last longer than the standard ARB + links takes this from an extravagance to just being common sense as far as I can see!
Hope this helps... if anyone has a clue how to make my steering lighter please let me know.