Doc Johnson has the
most functional dildos and sets (e.g. it is possible to attach/detach the suction cup, use the same dildo with a matching harness as a strap-on, ...). However they are made with plasticisers that may in the long run impose a health risk. So, if used regularely, better apply condoms. Also they come with a bad smell.
Although the Mr. Marcus replica is 9" long only about 6 1/2" are insertable(!) due to the non-flexible balls at it`s base. A better fit for you would be the Rob Piper model which is about 10 1/2 inches long at just above 8" insertable length, but it is quite girthy (6.7 inches around). An alternative would be Prince Yahshua which has the same length, is slightly bent upwards and is about 6" around.
Doc Johnson`s Ultraskyn Rob Piper...
Doc Johnson`s Ultraskyn Prince Yahshua...
For body safety i prefer Vixen Creations` VixSkin series, which also has a real look-and-feel. Made of 100% platinum silicone and it`s easy to clean. For each dildo you can choose from three colors ("vanilla", "caramel" and "chocolate"). The "Outlaw" seems to best serve your needs. It is 8 1/2 inches long and about 6 inches around. Not sure about the suction functionality though.
The VixSkin Outlaw chocolate...
Regards.