Both in ACL (6.2 EE) and LW (4.3.6 PE), selecting restarts that need some user intervention, like USE-VALUE, make slime hang.
CL-USER> foo [hit 3 for USE-VALUE] enter an expression which will evaluate to a new value: 1
and then nothing happens.
Andras
[Fresh CVS slime, Emacs 21.2.1, Linux]