What'sS your opinion on ProAc Studio 140

Dear All,

I am using Marantz SACD machine of model 7001 and soundmaster's integrated amplifier of 88.3 with 4 KT88 bulbs. And I am currently using Tannoy F4 Mercury speaker. Some one suggested me to use ProAc Studio 140. Should I change? Can you give me some opinions? Thanks a lot