The HTC Advantage X7500 and X7510 are ‘pocket PCs’ for those that absolutely require Windows Mobile on a bigger screen: a very unique device that still has demand.
The main difference between the X7500 and X7510 is the internal storage: the X7500 has 8GB and the X7510 has 16GB. Also the X7500 comes with Windows Mobile 5 whilst the X7510 comes with Windows Mobile 6.1 Professional. However the X7500 can be upgraded to Windows Mobile 6.
External storage is also an option on both models as they both support miniSD.
Both models also come with TV-out support and Blackberry Push Email Client.
The battery is twice the size of a standard mid-range smartphone’s so a full charge should go a long way.