If the code is already in PowerBuilder then converting the applications you have to VS and/or Java is going to cost a HUGE amount of money, the applications will run many orders of magnitude slower (which will then require significantly more money to buy faster hardware), and like as not, NEVER GET DONE.
I cannot tell you how many projects I've run into where PowerBuilder applications were being "sunset" in favor of Java and/or VS and were subsequently cancelled due to cost and/or lack of performance.
True story; my current main client brought me on back in 2008 to baby-sit their customer service application (written in PB 10 and supporting 500+ users) for the last year of its life while the new Java app was being finalized. Due to budget cuts they let me go in 2009 figuring "enough" had been done to allow the PB app to live long enough. In 2011 they brought me back part time to upgrade the app to PowerBuilder 12.5 and Windows 7; a project which I completed in a whopping 29 hours. As they had budgeted 1,000 hours for me to complete the project, they just kept handing me bit work to keep the app limping along until its (new) scheduled retirement date of 2013. Not surprising, my part time gig got extended into 2012 and then 2013 with the sunset date being extended to 2014.
Two weeks ago it was revealed that the Java app had thus far consumed between 45 and 60 million dollars (depending upon which group you talk to), and after all of money and years of development it was still only able to do about 25% of what the PowerBuilder app could do. Needless to say, when the gross expenditures leaked out, there was a management shakeup and within days the new Java application was "suspended" until further notice.
And the PowerBuilder app? It is now the "new" (again, it was initially developed back in the PowerBuilder 3/4 era) enterprise customer service application; I'm suddenly being handed more than enough work to keep me busy full time and it looks like we're going to be nosing around for another PowerBuilder resource by year's end.