Other than sound chips for electric's I can't see the point in sound chips, having chuffing, hissing or 'growling' (for diesel outline) from model loco's without the correct visuals also being emitted too just looks and sounds pointless to me, technology for technology sake - true - close ones eyes and the effect *is made*, but then why bother with the actual model, why not just listen to one of those old "Transacord" or equivalent recordings?!
Save you GBP45, that money goes a long way towards another loco or buys one or two coaches...