Hi Tim,
speaking as a connisure, or is that connisewer, as a P*** artist, I can highly recommend Waitrose`s solera jerezana dry amontillado & dry olorosa at about £6.99p a bottle they are both excellent. If you want to push the boat out a bit (xmas is coming) try their Lustau east india solera sherry about £11 a bottle, a tad pricey but oh so good.
Adrian.