Rent a car or train?

Yeh I know that public transportation is excellent in most regions but when you travel with the luggage and do not stay for more than two days in one place and flexibility that car gives you.....
We are planning 8 days (+ 4 days in Tokyo) Tokyo-Fuji-Nara-Himenji-Nara-Takayama-Matsumoto-Tokyo round trip.

What difficulties should we expect when driving this route? Traffic/unclear signs/parking/other problems???
Would you suggest driving or train?

Tokyo-Fuji-Nara-Himenji-Nara-Takayama-Matsumoto-Tokyo round trip.

What difficulties should we expect when driving this route?

1) Distances: it is over 600 kilometers from Tokyo to Himeji: a full day of driving vs. 3 hours by shinkansen

2) Difficult orientation in Tokyo and Osaka. They are huge, confusing cities to people who are not familiar with them.

I definitely recommend trains to travel between Tokyo and the Kansai region (Nara, Himeji), but from Takayama to Tokyo, a car can be a pleasant alternative to public transportation.

I am a confirmed driver - just TRY to take my car away - here in Japan, but I agree that the legs from the Kanto side (Tokyo) over to Kansai - Nara, Himeji - is too far. It'll eat up way too much time and the expressways, while fast and having totally interesting rest stops, are kind of boring.
While I don't like driving IN Tokyo (and there's no reason to, the subways & trains are too good), driving THROUGH or AROUND Tokyo is not the nightmare it used to be. You should be familiar with the names of the major expressways leaving Tokyo, as they are good indicators of direction, as well as the numbering system of the inner expressways (Shuto). Get a good map for that.
Parking is also expensive and hard to find in Tokyo.
Outside of Tokyo - Takayama, Matsumoto, don't know about Nara and Himeji - there is ample well-marked and reasonably priced parking (at least, in my opinion) and the roads are well-marked.

one problem for some foreign tourists is driving on the left side of the road!
I have never driven in Europe or Japan as this give me a chance to use their great fast trains. I haven't found it a problem, even when moving from town to town every couple of days.

Thanks for your answers!
I dont mean to go to Himenji directly from Tokyo, but to stay in Fuji five lakes and next day to stay in Kyoto - similar on the way back - Takayama is first stop on the way to Tokyo. In this way I split the road to ~300 km parts and enjoy the flexibility of car. What do you think? Btw, is there GPS in english in Japan?

Hi Alex.

My recommendation is:
1.Move Tokyo to Kansai region directly by train.
2.Visit Himeji and Nara(but Kyoto is recommended more) by Train.

3.Move to Gifu city and rent a car then drive to Takayama.

4.Drive Takayama to Matsumoto where is very deep and high mountain area. Note, the some roads are closed in winter because of snow.

5.Drive ''Venus line'' mountain road south-east of Matshmoto.

6.Drive around Mt.Fuji and go to Hakone - Izu if possible.

7 Back to Tokyo.

The problem is the best season for driving is differrent by the area. For #4 and #5, summer may be best because weather is still cold and snow remains on the mountain even in May. But for #6, April to May is the best as Mt.Fuji in summer is not so beautiful.

For your information, following is a map filled with marks the places where I visited.
http://www.mc-taichi.com/map/index.php
Sorry for all written in Japanese, but it may be help you to know rough geography.

Thanks and have a nice trip.

If you split the long journeys in smaller ones is a good idea, however, you have only 8 days. Considering the amount of time you have available, I recommend to use more time-efficient transportation, i.e. shinkansen, for the long distance trips.

Thank you guys,
I'll use shinkansen for long distances, as you suggest.
Alex