Paolo Di Canio has been busy for most of the summer, with the current count at nine new signings, and their pre-season trip to the Barclays Asia Trophy proved to be fruitful.
A win over Tottenham was followed by a narrow defeat at the hands of Manchester City in the final, and they now head to Denmark to complete their preparations.
"The quality of players that the manager has brought in is pleasing," O'Shea said.
"[Former Juventus midfielder Emanuele] Giaccherini has not been here long, but already you can see from his first touch he's got that bit of class - it's very pleasing on the eye.
"His link-up play with the strikers looks good and if we can get him fully fit and get Jozy Altidore banging in goals, alongside Sess [Stephane Sessegnon], who's looking fantastic, it's going to be exciting.
"We have got a lot more attacking options than we have had before - the new players, [Steven] Fletcher when he comes back, [Connor] Wickham and Ji [Dong-won], who's come back from Germany looking a lot sharper.
"There's going to be a lot of competition for places, which can only be a good thing and should see us push our way up the table.
"The new players are getting on fantastically well. They all seem to be good lads and they have taken to the atmosphere amongst us.
"Some of the training sessions have been a bit of an eye-opener for them in terms of the intensity that's demanded so early on, but I think they realise they are going to benefit from it."