RS fanboy here after getting shafted by Farnell for 3 orders in a row on allocated stock items that suddenly disappeared at the packing step. Usually slightly more expensive than Farnell with worse MOQs, particularly on older ICs when you need one for a repair job. But they will fix any cock ups instantly, the call centre staff aren't idiots and the stuff actually gets to you next day in one single consignment not from all over the place by different carriers.
Farnell has the best parametric search implementation, but the RS one actually has useful data in it so Farnell lose there as well.
The thing that annoys me is I can do an order from Tayda in Thailand with 50-70 lines in it for less than $10 and it turns up spot on every time. Farnell can fuck up a 4 line order for £500 and send it in three consignments.