Although I have no personal experience with the tecnodec or the P25 those in the know whose opinion I would trust says it is a lateral move.
If you're going to take the trade-in hit better to make a definitive move upward to, for example, a Nottingham Spacedeck, or a Michel Gyrodec.
I have always felt personally that incremental trade-ups are a waste of money, and it is preferable to wait until sufficient funds are accumulated to make a significant step up, or simply decide that it is not possible to justify a big jump.
If you're going to take the trade-in hit better to make a definitive move upward to, for example, a Nottingham Spacedeck, or a Michel Gyrodec.
I have always felt personally that incremental trade-ups are a waste of money, and it is preferable to wait until sufficient funds are accumulated to make a significant step up, or simply decide that it is not possible to justify a big jump.