The 10-colour model, which has Inpress Control and CutStar, will be installed this month, with plans for it to go into full production by the middle of February.
Group managing director Andrew Jones said: "The key with the new XL 105 is that it is a better build.
"It really does run at 15,000sph and with CutStar it provides a really industrialised solution."
The press will primarily be used for magazine production at the Merthyr Tydfil-based company and also as back-up for the business' existing SM 102-12P.
Stephens & George ordered one of the first new generation XL 105 long perfectors, an eight-colour, just before its official launch at Drupa.
Jones said it is achieving at least 35% better productivity than the SM 102 series presses, and in November it topped the 5m impressions-a-month mark.
He said: "The problem remains that the industry is still cutting prices so we are running faster to stand still. You have to have the right technology to remain in the game."
Turnover of the 240-staffed company last year was £20m, and it has budgeted for a slight increase in the current financial year.
Welsh magazine printer adds to armoury with Speedmaster perfector
Magazine printer Stephens & George has boosted its productivity after installing a Heidelberg Speedmaster XL 105 long perfector for an undisclosed sum.
